1. Field of the Invention (Technical Field)
The present invention relates to force control for attractive magnetic levitation, particularly for trains.
2. Background Art
The primary parameter that must be controlled in attractive magnetic levitation is lift force. Lift force can be measured with strain gauges, but these devices are extremely sensitive to the thermal environment. Force can be predicted as a function of gap, lateral displacement, and current, but the prediction is very sensitive to measurement errors in gap and current. Better, more robust force prediction is needed, which is provided by the present invention.